Bobby Rahal said Thursday that he is "reasonably sure" his race team will participate in this year's Indianapolis 500, but it is doubtful it will be involved in the entire IndyCar Series season because of lacking sponsorship.

Rahal Letterman Racing, which is based in Hilliard, Ohio, had Ethanol as its sponsor last year and won the July race at Watkins Glen (N.Y.) International with Ryan Hunter-Reay driving, but that funding will not be available from the promoters of the corn industry.

Rahal said his deadline hasn't arrived for such a decision, in part because the team could have its cars prepared to race within two weeks, but time is running out. The season begins April 5.

"Let's face it, the economy is such that people are being awfully careful with their money," said Rahal, who is the first team owner to say his participation is in doubt for the IndyCar season. "The environment is not good, and we're being affected by it."

As a driver or team owner, Rahal been involved in the sport every year since 1982. He won the 500 as a driver in 1986 and as an owner in 2004 with Buddy Rice.

"Twenty-six years; long time," Rahal said. "But to be honest, unless pennies from heaven fall in our lap, I don't see, at this stage, getting the appropriate level of funding to put forth a good, competitive effort for the season.

"Indy is a whole different (financial) animal, but we don't want to just be there. We want to be competitive.

"If we sign a veteran driver, like Ryan Hunter-Reay, who drove for us last year and who we think the world of, we could probably put something together as late as the week before the first race. If we go with a young, untested driver, we would probably need to get him to one of the preseason tests, which would mean we'd need something put together sooner.

"In any case, we feel strongly we can have something in place for Indy. There's a lot of interest in that race because it's the crown jewel of our sport."

IRL spokesman John Griffin said a Rahal Letterman withdrawal from the series would be "a sad day for motorsports."

"Bobby's racing heritage, combined with the cachet and love for the Indy 500 David brought to the sport, has made RLR a formidable enterprise," he added. "Both Bobby and David have played great roles in the sport."

RLR, which is co-owned by talk-show host David Letterman, also has programs in the Firestone Indy Lights Series as a partner with Andersen Racing, its American Le Mans Series program and a new partnership with Formula BMW Americas.

The team raced in the now-defunct CART series from 1992 to 2003, winning one series title with three-time champion and 1986 Indy winner Rahal at the wheel, before moving to the IRL's IndyCar Series in 2004.

RLR's problems come almost exactly a year after the unification of the IRL's IndyCar Series and the Champ Car World Series — the successor to CART — ended 12 years of debilitating rivalry between the two American open-wheel organizations.

Car counts in the merged series were up last year — to as many as 28 — as was at-track attendance and TV numbers. But the economic crisis is taking its toll, just as it has in NASCAR, where teams have been forced into mergers, many have laid off employees and some will field fewer cars.

Griffin said the IndyCar car count right now, excluding RLR, stands at 18.

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